Time-resolved fluorescence detection of mosaic DNA chip

Area of Science:

• Biotechnology and Bioengineering
• Analytical Chemistry
• Molecular Biology

Background:

• Mosaic DNA chips offer a platform for high-throughput analysis.
• Existing fluorescence detection methods can lack sensitivity and specificity for complex arrays.
• Time-resolved fluorescence (TRF) offers potential advantages in signal-to-noise ratio and reduced background interference.

Purpose of the Study:

• To establish a time-resolved fluorescence (TRF) labeling and detection strategy for mosaic DNA chips.
• To demonstrate the capability of TRF detection to differentiate between perfect DNA matches and various mismatches.
• To evaluate TRF as a viable alternative to conventional fluorescence detection in biochip applications.

Main Methods:

• Synthesis of oligonucleotide sequences directly on glass slides, followed by creating a mosaic DNA chip.
• Development of a TRF labeling method using 4,7-bis(chlorosulfophenyl)-1,10-phenanthroline-2,9-dicarboxylic acid (BCPDA) and avidin-biotin amplification.
• Utilizing Europium (III, Eu3+) complexation and dissociation for TRF signal generation upon DNA hybridization and mismatch detection.

Main Results:

• Successful establishment of a TRF detection format on the mosaic DNA chip.
• Demonstrated discriminatory TRF signals for perfect match, one-base mismatch, two-base mismatch, and three-base mismatch DNA hybridization.
• Characterization of fluorescence spectra and lifetimes, confirming the TRF detection mechanism.

Conclusions:

• The developed TRF detection method provides sensitive and specific discrimination of DNA sequences on mosaic chips.
• TRF detection is a potential alternative to conventional fluorescence detection, particularly for mosaic DNA chip labeling.
• This advancement has significant implications for the development of advanced biochips and biosensors utilizing TRF technology.